A virtual network forwarding engine such as NSX Edge®, unlike those traditional physical network router or switch, has thousands of logical routers and logical switches and tens of thousands of logical ports. In contrast to a network packet in a physical router or switch that may only hop from one port to another, the forwarding path in one NSX Edge of today may pass through twenty or more logical ports and interfaces. The number of the logical entities that one packet may traverse in one such virtual network forwarding engine creates network reachability issues that complicate troubleshooting efforts.
Unlike control plane or management plane engines that readily provide GUI user interfaces to assist troubleshooting by network admins, the data-forwarding plane usually rely on CLIs (command line interface) as the user interface for debugging network forwarding issue. Such a CLI typically displays only the configuration and forwarding information. This is insufficient information for troubleshooting the operations of a virtual network forwarding engine, because the network admin doesn't even know which logical entity to display. Such troubleshooting effort generally requires significant investment in human labor in identifying the relevant logical entities from a sea of meaningless computer generated identifiers.